Multiple chine boat hull



May 6, 1952 A. A. STEELE I MULTIPLE CHINE BOAT HULL 2 SHEETSSHEET 1Filed Dec.

INVENTOR. ARCHIE A. STEELE BY (MA l t ATTQRNEY y 1952 A. A. STEELE2,595,422

MULTIPLE CHINE BOAT HULL Filed D60. 8, 1945 2 SHEETS-SHEET 2 1111111114'IIIIIIII. .u

'IIVVENTOR. ARCHIE A. STEELE ATTOR N EY Patented May 6, 1952 UNITEDSTATES PATENT OFFICE 2,595,422 MULTIPLE CHINE noA'r HULL Archie A.Steele, Los Angeles, Calif.

Application December 8, 1945, Serial No. 633,647

3 Claims. 1

My present invention relates to a hull for a combined sail and motordriven boat, having relatively high speed under motor power and undersail as compared to usual motor and sail propelled boats, as the resultof a novel arrangement of body or superstructure with a keel and aspecific arrangement of chines to provide a vessel suitable foroperation in all kinds of weather, either under sail or under motorpower at speeds above the generally accepted maximum speed fordisplacement types of hulls. It is an object of the present invention toprovide a boat hull having the general characteristics disclosed in theabove, but having improved characteristics under both mechanical andsail power, and especially having greater speedunder sail for a givensize of vessel and spread of sail. a

It is an object of the invention to provide a combined sail andmotor-driven vessel of the.

character'referred to in the foregoing, having increased speed undersail by reason of the provision of a chine on each side'of the bottom ofthe boat body which lies, through a portion or all of its water linelength, in a substantially vertical plane disposed parallel to themidline of the hull,

this arrangement providing, when the vessel is heeled over, relativelylong and straight surfaces in engagement with the water, the oppositeside 01' the ship lifting partly out of the water and allowing the shipthus heeled to sail along the straighter lines and surfaces provided asthe result of the joining of the top and bottom surfaces at therelatively straight chine which is in engagement with the water.

A further object of the invention is to provide a hull of the characterset forth in the foregoing having side walls and chines which extendalong relatively straight parallel lines from a point near the front ofthe vessel to the stem, the vessel thus having a deck area which issubstantially as wide at the stern as in the midportion thereof.

A further obiect of the invention is to provide a hull having longrelatively straight and parallel chines along the sides of the bodyportion of the hull, this hull having adjacent the stern portion thereofa secondary or auxiliary chine which cooperates in the hull structure inproducing comparatively fiat sections in the after part of the hull,which keep the vessel from squatting excessively from cavitation due topropeller action.

A further object of the invention is to provide a hull for a sailingvessel which has greater lateral stability than found in accepted typesof sailing boat hulls, without reduction in the sailing qualities of theboat. In view of this, it is possible for the sail boat incorporating myinvention to carry more sail area than the usual sailing vessel.

It is an object of the invention to provide a sail boat hull whichminimizes the production of current eddies, by reason of the provisionof chines parallel to the keel whereby paths of flow for the water aredefined, wherein minimum disturbance of the water is achieved.

Further ob ects and advantages of the invention may be brought out inthe following part of the specification.

Referring to the drawings which are for illustrative purposes only,

Fig. 1 is a side view of a vessel invention. Fig. 2 is a top plan viewof the hull of the vessel Fig. 3 is the section indicated by the line3-3 of Fig. 1.

Fig. 4 is the'section outline on the plane indicated by the line 44 ofFig. 1.

Fig. 5 is the section outline on the plane indicated by the line 55 ofFig. 1 with the rudder removed.

Fig. 6 is the section outline on the plane indicated by the line 66 ofFig. 1.

In Fig. 1' I show a boat hull I 0 and a superstructure consisting of therigging ll comprising a mast i2 and sails l3' which form no part of thepresent invention. For th purpose of distinguishing between the upperand lower'parts of the hull I0, I have divided the same substantiallyalong the water line into a keel I4 and a body IS. The body I5,referring to Fig. 4, may be regarded as that portion of the hull lyingbetween the side walls It, and the keel l4 may be considered as thatportion of the hull lying between the keel, side walls I1.

In the variousviews, which are schematic in character, I have shown adeck i8 which, as shown in Fig. 2, has a rounded front end [9, approximately parallel and slightly bulging side edges 29, and a somewhatsquare rear end2l. The side walls I! of the keel l4 flare upwardly andoutwardly to meet the lower edges of the body side walls i6 at chines 22which maybev either sharp or rounded. The side walls [6 of the body andthe side walls I! of the keel l4 embodying my are formed in suchcooperative relation that the:

3 will support the hull in the water under load so that the lowestportions of the chines 22 will substantially coincide with the loadwater line.

As shown in Fig. 2, the chines 22 are substantially straight andparallel, as viewed from above, throughout a portion of the length ofsuch chines which engage the water. In the preferred embodiment shown,the chines 22 lie in vertical parallel planes from a point ahead to apoint aft of the engagement of the chines with the water. Optimumresults are achieved when the chines extend straight from the rear endof the hull, as viewed from above in Fig. 2, to the points 21' above theload water level where such chines curve inward to join the stem of thehull. The chines 22 throughout a material portion of their length lie invertical planes parallel to the longitudinal median plane P of the hull.

The upper or outward portions of the side walls ll of the keel l4 formbottom walls for the body [5, and the upper or outer portions of thewalls I! are curved soas to provide inwardly of the chines 22 invertedchannels 30 which have their inception ahead of the plane indicated bythe line 3-3 of Fig. l and fade out substantially at the plane indicatedby the line 44 of Fig. 1, these channels having the purpose of directingair under the bottom of the body l5 when the craft is moving forward,thereby reducing the wetted surface, and cutting down frictional drag.The load water line of the hull is represented in Fig. 1 by two separatelines 32 and 33, the first of these lines 32 indicating the load waterline when the vessel is under sail with substantially no side wind, andthe line 33 represents the load water line when the vessel is movingforward under power provided by propeller means 34 operated by an engine35. The chines 22 coincide with the forward direction of travel of thevessel and therefore minimum resistance to forward travel is attained.This condition exists when the hull is level in the water and when it isheeled over as indicated by dotted lines It in Fig. 4. Between the chinewhich is in the water and the median plane P of the hull the upper orouter portion of the side wall I! defines an inverted channel 30', Fig.5, which extends longitudinally beneath the body portion l5 andconstitutes a continuation of the inverted channel as disclosed in Figs.1 and 3.

The side walls I! of the keel portion 14, as shown in Figs. 1, 2, 5, and6, are formed so as to provide within the limits of the chines 22auxiliary chines 38 which start near the fore to aft middle of the hulland extend rearward along inwardly curving lines so as to meet at aposition 39 slightly to the rear of the plane indicated by the line 6-6of Fig. 1. These chines 38 coincide substantially with the horizontalplane'defined by the load water line 32 and have the purpose ofresisting the action referred to as squatting when the vessel is beingdriven under power, such squattin consisting of a marked lowering of thestern of the vessel due to cavitation resulting from propeller action.The hull structure described in the foregoing accomplishes a number ofimportant results as follows:

When the vessel is heeled over as shown by dotted lines [0 of Fig. 4, aportion of the body volume is included in the displacement volume of thehull so that the midline section of the hull on the opposite side islifted partly out of the water, and the area of hull surface inengagement with the water is not materially increased over the surfacearea contact of the hull with 4 the water when the hull is level. Also,the lateral lines extending longitudinally of the hull, and inengagement with the water, are substantially straight and coincidentwith the forward motion of the travel of the hull.

When the hull is heeled over under sail, the load water line greatlyincreases so that the theoretical speed, determined by the formula 1.5times the square root of the water line length, in-

creases.

The keel M of the hull has a vertical dimension or depth at least asgreat as the depth of the body 15, and may be of standard or centerboard type in smaller boats. In larger craft the keel I4 is made hollowto provide useful space. For example, the engine schematically indicatedat 35 will be disposed in the space provided by the hollow keelconstruction.

I claim as my invention:

1. In a hull for a sail and power vessel, the combination of: a bodyhaving side walls, intermediate portions of which are in parallelrelation to the longitudinal center line of the hull; a keel extendingdown from said body, said keel having a depth at least as great as thedepth of the body; main chines on the lateral portions of said bodystarting at the front end of the body above the water line and droppingbelow the water line as they extend rearwardly, the portions of saidchines which drop below the water line being disposed in planes whichare substantially vertical and parallel to the longitudinal axis of thehull; and auxiliary chines on said keel positioned between said mainchines and the median vertical plane of the hull and extendingrearwardly from a position midpoint of the hull.

2. In a hull for a sail and power vessel, the combination of a bodyhaving side Walls, the intermediate portions of which are in parallelrelation to the longitudinal center line of the hull; a keel extendingdown from said body, said keel having a depth at least as great as thedepth of the body; main chines on the lateral portions of said bodystarting at the front end of the body above the water line and droppingbelow the water line as they extend rearwardly and again rising abovethe water line at the rear of the body, the portions of said chineswhichdrop below the water line being disposed in planes which aresubstantially vertical and parallel to the longitudinal axis of thehull; and auxiliary chines on said keel positioned between said mainchines and the median vertical plane of the hull and extendingrearwardly from a position midpoint of the hull, said keel being formedso as to provide downwardly faced channels between said auxiliary chinesand said main chines.

3. In a hull for a sail and power vessel, the combination of: a bodyhaving side walls, intermediate portions of which are in parallelrelation to the longitudinal center line of the hull: a keel extendingdown from said body, said keel having a depth at least as great as thedepth of the body; main chines on the lateral portions of said bodystarting at the front end of the body above the water line and droppingbelow the water line as they extend rearwardly, the portions of saidchines extending from the rear ends thereof to a position ahead of thepoint at which they drop below the water line being disposed in planeswhich are substantially vertical and parallel to the longitudinal axisof the hull; and auxiliary chines on said keel positioned between saidmain chines and the median vertical plane ARCHIE A. STEELE.

REFEa-Eivops CITED The following references are of record in the file ofthis patent:

6 UNITED STATES PATENTS Number Number Name Date Manker :Juiy 12, 1904Ferron 4 Feb. 7, 1928 Durand "May 14, 1929 Hillmann Mar. 3, 1931 VanWienen Oct. 6, 1931 Steele Mar. 13. 1945 FOREIGN PATENTS Country DateFrance Feb. 15, 1909 Great Britain Sept. 19, 1918

